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copied!<h2>A nested <code>switch</code> is an option...</h2> <p>This uses two switches, but the second is not triggered in the <code>default</code> case so has a <em>slightly</em> better performance profile than just two in-line switches.</p> <pre><code>switch($x) { case a: case b: case c: executeSth(); switch($x) { case a: executeA(); break; case b: executeB(); break; case c: executeC(); break; } break; default: ... } </code></pre> <h2>Alternatively, a variable function may do the job...</h2> <p>This is a PHP option which may work, though a lot of people don't like variable functions. This is probably the best option if you want to totally remove nesting & repetition.</p> <pre><code>switch($x) { case a: $function = "executeA"; break; case b: $function = "executeB"; break; case c: $function = "executeC"; break; default: ... } if(isset($function)) { executeSth(); $function(); } </code></pre> <p>I've also made a little <a href="https://eval.in/46491" rel="nofollow">live test bed here</a>, if anyone wants to test their PHP solutions work before posting them (<code>case 10</code> should <code>executeSth()</code> and <code>executeA()</code>, <code>case 20</code> should <code>executeSth()</code> and <code>executeB()</code>, <code>default</code> should <code>executeDefault()</code>).</p> <h2>In C++, you can use a function pointer to achieve the same as the above</h2> <p>I had a total brain fart when I wrote this, thankfully idipous reminded me that we can do this with a simple function pointer.</p> <pre><code>// Declare function pointer int (*functionCall)() = NULL; // In switch statement, assign something to it functionCall = &execute; // After the switch statement, call it int result = (*functionCall)(); </code></pre> <p>Note: I'm out so haven't checked the syntax on these. The syntax I've used is C syntax and may require some small changes to work in C++.</p>

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